This invention relates to electrostatic flocking systems. More specifically, this invention relates to improved apparatus for entraining flock fibers in an air stream and for delivering entrained flock fibers to an article being coated.
In the prior art, a wide variety of electrostatic flocking systems are well known. Typically, such systems comprise a vibratory hopper or a so-called fluidic bed for shaking flock fibers into a position for entrainment with an air stream which delivers the fibers to an applicator gun. It has been found, however, that prior art flock entrainment equipment requires undesirable quantities of air flow and excessive air pressures for delivery of continuous, uniform quantities of flock fibers to a gun. In fact, the high air flow requirements of prior art systems have usually required the entrained flock fibers and the propelling air stream to be separated at the applicator gun to prevent excessive quantities of the fibers from being blown past or bouncing off the article being coated. See, for example, U.S. Pat. No. 3,551,178.
The invention of this application overcomes the problems of the prior art by providing an electrostatic flocking system having an air flow pump for picking up relatively high quantities of flock fibers in a relatively low pressure entraining air stream. Further, the invention of this application provides a novel outlet nozzle for an applicator gun for use in combination with the low pressure air flow pump for assuring proper air and electrostatic delivery of flock fibers from the applicator gun to an article being coated.